The Three Leaps of the Human Evolution
Humans are the only living being on earth endeavoring in self
investigation. Then one can ask
if the evolution processes regarding humans are specific to this species only,
or not. My answer is “yes”. This species had to experience three consecutive
and important leaps before becoming modern human.
Initially the science of Anthropology has intuitively linked the bipedalism
of the human species to its intellectual capacity. As the fossils and bones of
the Australopithecine started to
appear, subsequent work and research continued to support the initial
intuitive assumption. The mechanism of evolution for all species can be
explained as follows: Small changes in the environment and habitat create
selective pressures on the organism, and the organism gives adaptive response to
them. As these changes accumulate over a long period of time, speciation
happens. This is how science explains the process of evolution. But such an explanation,
regarding the evolution of human did not, until now, give satisfactory results.
For the following reasons:
Human
are different when compared to other species on earth. But the same process of
evolution has been assumed to apply for both human and other species.
Accordingly, the human lineage separated from a common ancestor about 6 million
years ago, and the mechanisms of natural selection resulted in forming the
modern human.
Human
are very special and very different. These are the only living being on earth
endeavoring in self investigation. Then one can ask if the evolution processes regarding human are specific to
this species only, or not. My answer is “yes”. This species had to experience
three consecutive and important leaps before becoming modern human.
1) The Leap of Bipedalism
About 6-7 million years ago the lifestyle of a primate living in the
equatorial forests of eastern Africa was disrupted and changed drastically due
to rift formation. As a result of rifts and plateau formations several volcanic
eruptions created wildfires that carbonized the trees on which this primate was
living. Thus the primate had to abandon the carbonized trees. Since no food was
available in this burned out region the primate was obliged to search food in
the shallow waters. In order to search for food in water the primate had to
stand on two legs. This primate, for about 4 million years, hunted and gathered
food in shallow waters during daytime and during nighttime slept on carbonized
trees.
Such
a different lifestyle transformed the primate to adopt an erected
posture and bipedal locomotion. These transformations do
not stop until the biological architecture and kinematic functions of the body
come to stabilize in the most economical posture. The final stage of this
transformation is when the body reaches the form of a modern human.
If,
for example, the process towards becoming modern human stopped at some point in
between these 6 million years and its genetic formation came to halt, the
species could not continue to survive with its partially transformed biological
architecture. This is because the locomotion of such a living being would not
be stable and balanced. Especially, when it comes to run, the body would not
keep its balance and would fall. No species could be able to survive and keep
existing with such a body. This is why the required transformation towards the modern
human body posture kept its course.
All variants of hominid types encountered up to now are transitive
variations towards the modern human. They are not basically different species
(Kaynak 2012, 2013). The rift and plateau formation started from the north and
in time advanced towards the south. This may be why different primate groups
have been forced to adopt bipedal locomotion over different periods of time.
This is also why they were in different stages of the journey towards the
modern human and were considered to be different species. In spite of defining
the fossils until about two million years from present as being Australopithecine and as being Homo from that time on, they are not
different species but are transitive variants on the journey towards becoming modern
human.
2) The Leap of Mental
Overturning
When about 2 million years ago the body erection reached a certain angle,
the embryo made an adaptive response in accordance with this vertical body posture.
While previously the embryo attached its placenta to the abdominal region, it
started to attach the placenta to the dorsal side of the erected mother.
Previously the head of the embryo was formed towards the birth canal, but now
it started to be formed towards the mother’s diaphragm.
Modern human embryos correct this “Mental Overturning” which happened
about 2 million years ago by turning towards the birth canal at the seventh
month of the pregnancy, and preparing for birth. This is the mental overturning
that started the growth of the cranium as well as the brain.
3) The Leap of Mental
Threshold
The
present day chimp, with its 350 cc brain can tear away a tree branch and attack
its enemies with it. It can also pick up a stone and throw it to its enemy.
When the predator jaguar approaches Capuchin monkeys of the Brazilian forests,
they climb the cliffs and roll down an avalanche of rocks and stones, forcing
the jaguar to retreat. These capuchin monkeys can also make use of stones in a
sophisticated manner in order to break coconuts. The chimps can also make use
of a stone for cracking fruit seeds.
In a way, both primates use the stone as a tool as well as a weapon. Chimps
make use of thin twigs for hunting termites and collect honey from beehives. If
a chimp with its 350 cc brain can do such things, one should wonder what its capabilities
would be, if it had a 500 cc brain.
After chasing its enemy, the chimp throws the stick and does not say to
itself: “This stick has served me effectively; I better keep it for another
occasion”. If the chimp had a brain of 500 cc, would it say: “I better keep
this stick and even improve it”. The chimp may not think so with 500 cc brain,
not even with a 550 cc or even a 600 cc brain. But there will be a time and a
brain capacity that such a thought will occur.
This is the critical point which I have labeled as the Mental
Threshold. Once this mental threshold was transcended, the hominid that
held a stone in one hand and a stick in the other; had the courage to intrude
into the hunting zone of any animal including the worst predator.
When it reached the capacity to influence his prey as well as his predator with the help of sticks and stones, the
hominid departed from the rift in order to conquer the world. After the mental
threshold happened the hominid became cognizant of his nakedness, realized his
selfness and came to understand that sticks and stones could be used as
weapons.
The human mind is the result of the incredible adaptive responds given by
the embryo to the vertical body posture.